Why is weight-based dosing important?

Weight-based dosing is important because the same flat dose of medication may be too much for a small person or too little for a large person. Children especially require weight-based dosing because their bodies process medications differently than adults.

How do I convert pounds to kilograms?

To convert pounds to kilograms, divide the weight in pounds by 2.20462. For example, 150 lbs ÷ 2.20462 = 68 kg. Our calculator handles this conversion automatically when you select 'lb' as the unit.

What if the calculated dose seems too high?

If the calculated dose seems unusually high, double-check that you've entered the correct dose per kg as prescribed. Many medications have maximum dose limits regardless of weight. Always consult the prescribing information or a healthcare provider if you're unsure.

General Dose Math

mg/kg Dosage Calculator

Calculate medication dosage based on body weight using the mg/kg formula. Essential for weight-based dosing in pediatric and adult medicine.

mg/kg Calculator

Calculate medication dosage based on body weight using the mg/kg formula. Essential for weight-based dosing in pediatric and adult medicine.

Patient WeightEnter the patient's body weight

Dose per kgPrescribed dose in mg per kg of body weight

mg/kg

Doses per DayHow many times per day the dose is given

doses/day

This calculator provides mathematical estimates only. Always verify dosages with a qualified healthcare professional before administering any medication.

Important Disclaimer

This calculator provides estimates for informational purposes only. Always consult a healthcare professional before making medical decisions.

About This Calculator

The mg/kg dosage formula is the foundation of weight-based medication dosing. This calculator helps healthcare providers, nurses, and caregivers determine the correct medication amount based on a patient's body weight. Weight-based dosing ensures that patients receive an appropriate amount of medication proportional to their size, which is especially critical in pediatric care.

How It Works

Simply enter the patient's weight (in kg or lb), the prescribed dose in mg/kg, and how many times per day the medication is given. The calculator instantly computes both the single dose and the total daily dose. The formula used is: Dose (mg) = Weight (kg) × Dose per kg (mg/kg).

Frequently Asked Questions

mg/kg dosing is a method of calculating medication doses based on body weight. The dose is expressed as milligrams of medication per kilogram of body weight (mg/kg). This ensures patients receive an appropriate amount relative to their size.

Clinical Review

Dr. Igor I. Bussel, MD

Board-Certified Ophthalmologist

Dr. Igor I. Bussel is a board-certified ophthalmologist and fellowship-trained surgeon affiliated with the University of California, Irvine (UCI), the Gavin Herbert Eye Institute, and the UCI School of Medicine.

Last Updated: 2025-01-05

Sources & Guidelines

Medically Reviewed

Evidence-Based

Updated 2025-01-05

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References

Reviewed by: Clinical Review Team (PharmD, RPh)

Last updated: 2025-01-05